A.J. Allmendinger and Michael McDowell will each get new crew chiefs, according to ESPN.

Jimmy Elledge will take over for Ricky Viers at Red Bull Racing’s no. 84, driven by Allmendinger, this weekend at Chicagoland Speedway.

Elledge most recently was crew chief for Juan Pablo Montoya at Chip Ganassi Racing for three races before being let go.

Peter Sospenzo will replace Bill Pappas as crew chief for Michael Waltrip Racing’s No. 00, driven by McDowell. He will assume crew chief duties starting at Indianapolis Motor Speedway.